Philae landing on the nucleus of Comet 67P C-G |
Philae landing on the nucleus of Comet 67P C-G |
Sep 27 2014, 01:54 AM
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#31
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Member Group: Members Posts: 148 Joined: 9-August 11 From: Mason, TX Member No.: 6108 |
The latest NavCam composite shows that the left (main lobe) side of the valley seems to have cliffs with deep shadows, possibly vents. Now, seeing the line of boulders in the valley, I have a more distinct impression of gases from both sides of the valley impinging in the middle, creating on one hand a zone of stagnated velocities in which levitated boulders could lose escape velocity and drop down along that preferential zone, and on the other hand forming a plane of converged gas and dust. That plane would appear like a jet along the zone of impingement, and appear diffuse when viewed away from that plane. Just a thought, but it could explain why single sources for the "jets" have not been clearly identified yet, and why they appear variable based on direction.
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Don |
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Sep 27 2014, 03:12 AM
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#32
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Solar System Cartographer Group: Members Posts: 10256 Joined: 5-April 05 From: Canada Member No.: 227 |
That idea of jets forming where two or more broad cones of emission meet, channeling dust into sheets (two cones) or collimated jets (three cones) was referred to earlier in our discussions and originated with Jean Crifo 20 years ago (Icarus, 1995, v. 116, pp. 77-112).
Phil -------------------- ... because the Solar System ain't gonna map itself.
Also to be found posting similar content on https://mastodon.social/@PhilStooke Maps for download (free PDF: https://upload.wikimedia.org/wikipedia/comm...Cartography.pdf NOTE: everything created by me which I post on UMSF is considered to be in the public domain (NOT CC, public domain) |
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Sep 27 2014, 04:28 AM
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#33
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Member Group: Members Posts: 148 Joined: 9-August 11 From: Mason, TX Member No.: 6108 |
Thanks for the reminder, Phil. All very easy to visualize now.
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Don |
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Oct 15 2014, 01:19 PM
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#34
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Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
Site J confirmed as the landing site: ESA confirms the primary landing site for Rosetta
and we are given another image (actually a mosaic of two) from OSIRIS. (ADMIN EDIT) |
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Oct 15 2014, 01:44 PM
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#35
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Forum Contributor Group: Members Posts: 1374 Joined: 8-February 04 From: North East Florida, USA. Member No.: 11 |
It's not exactly flat is it ?
Those cliffs have to be at least 20 feet high ? |
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Oct 15 2014, 03:56 PM
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#36
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Senior Member Group: Members Posts: 2173 Joined: 28-December 04 From: Florida, USA Member No.: 132 |
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Oct 15 2014, 06:15 PM
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#37
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Senior Member Group: Members Posts: 4260 Joined: 17-January 05 Member No.: 152 |
It's not clear these are landing error ellipses, since I couldn't see any such description in the captions of either image. The caption of the latest image just says
QUOTE The circle is centred on the landing site and is approximately 500 m in diameter. The cross marking the central landing position in the old image is pretty close (but not exactly) at the centre of the new red circle. There's no way to know if that's just plotting error or a slight adjustment in the central position. |
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Oct 16 2014, 07:42 AM
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#38
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Junior Member Group: Members Posts: 31 Joined: 3-August 14 From: Germany Member No.: 7229 |
I have not seen this very high close up of the landing site J posted here, so here is the image in full resolution. Many wonderful details! thank you ESA
-------------------- space scout
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Oct 16 2014, 11:32 AM
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#39
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Solar System Cartographer Group: Members Posts: 10256 Joined: 5-April 05 From: Canada Member No.: 227 |
http://blogs.esa.int/rosetta/2014/10/16/la...tes-from-30-km/
The individual images for the Osiris mosaic of the landing area are here, plus - very nice - two images for site C as well. Phil -------------------- ... because the Solar System ain't gonna map itself.
Also to be found posting similar content on https://mastodon.social/@PhilStooke Maps for download (free PDF: https://upload.wikimedia.org/wikipedia/comm...Cartography.pdf NOTE: everything created by me which I post on UMSF is considered to be in the public domain (NOT CC, public domain) |
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Oct 16 2014, 02:49 PM
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#40
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Senior Member Group: Members Posts: 4260 Joined: 17-January 05 Member No.: 152 |
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Oct 16 2014, 02:50 PM
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#41
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Senior Member Group: Members Posts: 4260 Joined: 17-January 05 Member No.: 152 |
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Oct 16 2014, 03:06 PM
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#42
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Senior Member Group: Members Posts: 4260 Joined: 17-January 05 Member No.: 152 |
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Oct 16 2014, 03:25 PM
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#43
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Senior Member Group: Members Posts: 2922 Joined: 14-February 06 From: Very close to the Pyrénées Mountains (France) Member No.: 682 |
I'm wondering how far we'll see once on the ground. If we were to land on a perfectly flat surface, horizon would be very very close I believe, but on THIS, it's hard to predict anything.
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Oct 17 2014, 07:15 AM
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#44
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Newbie Group: Members Posts: 14 Joined: 7-August 12 From: California Member No.: 6489 |
http://blogs.esa.int/rosetta/2014/10/16/la...tes-from-30-km/ The individual images for the Osiris mosaic of the landing area are here, plus - very nice - two images for site C as well. Phil Here's my version of a site J anaglyph... |
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Oct 17 2014, 11:15 AM
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#45
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Forum Contributor Group: Members Posts: 1374 Joined: 8-February 04 From: North East Florida, USA. Member No.: 11 |
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